From top: It has become tough to make a living from fishing on Dongting Lake. During the close season for fishing, crayfish provide a source of income. Hit by a serious drought, parts of Dongting Lake look like grassland. Photos by Fu Zhiyong / For China Daily

Dongting is the largest freshwater lake in China, but it is suffering from overfishing, pollution and other major problems, finds Liu Xiangrui in Yueyang, Hunan province.

Instead of being excited at the start of a new fishing season, 59-year-old Peng Dingguo, who has fished in Central China's Dongting Lake all his life, is gloomy. And he has good reason.

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The lake in Hunan province used to be rich in fish and sustain at least 30,000 fishermen, but the second-largest freshwater lake in China is suffering from pollution and over fishing.

The situation has led to water species being endangered and threatens the livelihoods of people like Peng, whose families have depended on the lake for generations.

Peng says fewer than 20 species of fish can be found in the lake nowadays, compared with more than 100 kinds in the past.

"There are fewer fish and they are smaller, while equipment like nets cost much more," he says. "We can't make ends meet. In 2011 we had a severe drought and had to borrow money to get by."

Illegal fishing has made the situation worse, he admits, and many of his colleagues have turned to harvesting crayfish instead.

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Meanwhile, the eastern and southern parts of the lake administered by Yueyang city, have attracted fishermen from seven nearby provinces, according to Tan Yiqi, a Yueyang fishery administration official.

There are currently nearly 20,000 full time or part time fisherman and 500 boats on the lake and its connected rivers, he says.